This paper presents the heating performance and energy distribution of a system with the combination of ground-source heat pump and solar collector or a solar-assisted ground-source heat pump system (SAGSHPS) by calculation and experiment. The results show that the average absolute error is less than 0.6 °C and the relative error is less than 5% under the pulse load when the analytical solution to the 2-D solid cylindrical source model is used for the SAGSHPS. The coefficient of performance (COP) of the SAGSHPS is 2.95–4.70. The average fluid temperature in the borehole heat exchanger can increase by 3 °C with the assistance of solar collector, which will improve the COP of the heat pump by approximately 10% from the experimental data. The energy contributions to the total heating load of soil, electricity and solar are 56.30%, 36.87% and 6.83%, respectively.

In order to investigate the effects of methyl ester moiety on polycyclic aromatic hydrocarbons (PAHs) and NO _x formation in biodiesel combustion, the combined models were developed based on detailed methyl butanoate (MB) oxidation model and n-butane model. Also, PAHs detailed reaction mechanism and NO _x formation mechanism were added to the detailed models to form the combined models. The combined models were used to compare the combustion of n-butane and MB in a shock tube simulation to understand the effects of methyl ester moiety. The results indicated that compared with n-butane, the methyl ester moiety in MB leads to different reaction pathways, more CO and CO₂ formation and less formation of PAHs precursors such as ethylene and acetylene. In addition, a better chemical insight into the effects of methyl ester moiety on NO _x formation was given, which will help to understand the combustion process of biodiesel.

A fault diagnosis model is proposed based on fuzzy support vector machine (FSVM) combined with fuzzy clustering (FC). Considering the relationship between the sample point and non-self class, FC algorithm is applied to generate fuzzy memberships. In the algorithm, sample weights based on a distribution density function of data point and genetic algorithm (GA) are introduced to enhance the performance of FC. Then a multi-class FSVM with radial basis function kernel is established according to directed acyclic graph algorithm, the penalty factor and kernel parameter of which are optimized by GA. Finally, the model is executed for multi-class fault diagnosis of rolling element bearings. The results show that the presented model achieves high performances both in identifying fault types and fault degrees. The performance comparisons of the presented model with SVM and distance-based FSVM for noisy case demonstrate the capacity of dealing with noise and generalization.

Hydrophilic degraded gelatin was modified with hydrophobic poly(ɛ-caprolactone) (PCL) via a chemical grafting route. Firstly, PCL with one hydroxyl end group was prepared by the ring-opening polymerization of ɛ-caprolactone (ɛ-CL) with tin (II) 2-ethylhexanoate as catalyst and n-butyl alcohol as initiator. Secondly, the PCL reacted with isophorone diisocyanate (IPDI) to prepare PCL with isocyanate functional group (PCL-NCO). Hydroxylamine was used to degrade gelatin by the cleavage between asparagine and glycine residues of gelatin. PCL-NCO reacted with the hydroxyl/amino groups of degraded gelatin in a homogeneous system and yielded the PCL modified gelatin copolymers. The gelatin grafted PCL copolymers were measured by means of XRD, FTIR, DSC and ¹H NMR. The results confirmed the conjugation of PCL onto gelatin chains. The PCL modified gelatin can be used as biomaterials owing to their biocompatibility and biodegradation.

In 2010, the first offshore wind turbine with integrated installation was established in Qidong sea area of Jiangsu Province, China, which led to the implementation phase of one-step-installation technique based on the design and construction of large-scale bucket-top-bearing (LSBTB) bucket foundation. The critical technique of LSBTB bucket foundation included self-floating towing, penetration with adjustment of horizontal levelness, removability and one-step-installation. The process of one-step-installation included the prefabrication of LSBTB bucket foundation in onshore construction base, installation and debugging of wind power, overall water transportation of foundation and wind power system, and installation of foundation and offshore wind turbine on the appointed sea area. The cost of one-step-installation technique was about 5 000 Yuan/kW, which was 30%-50% lower than that of the existing technique. The prefabrication of LSBTB bucket foundation took about two months. During the one-step-installation process, the installation and debugging of wind power and overall water transportation need about one to two days in sea area within 35 m depth. After the proposed technique is industrialized, the cost will be further reduced, and the installation capacity is expected to be up to 500 wind turbines per year.

Based on the introductions of a type of diaphragm-through connection between concrete-filled square steel tubular columns (CFSSTCs) and H-shaped steel beams, a finite element model of the connection is developed and used to investigate the seismic behavior of the connection. The results of the finite element model are validated by a set of cyclic loading tests. The cyclic loading tests and the finite element analyses indicate that the failure mode of the suggested connections is plastic hinge at the beam with inelastic rotation angle exceeding 0.04 rad. The suggested connections have sufficient strength, plastic deformation and energy dissipation capacity to be used in composite moment frames as beam-to-column rigid connections.

Asymmetric stereoscopic video coding can take advantage of binocular suppression in human vision by representing one of the two views in lower quality. This paper proposes a bit allocation strategy for asymmetric stereoscopic video coding. In order to improve the accuracy of bit allocation and rate control in the left view, a proportionalintegral-derivative controller is adopted. Meanwhile, to control the quality fluctuation between consecutive frames of the left view, a quality controller is adopted. Besides, a fuzzy controller is proposed to control the variation in quality between the left and right views by comparing the PSNR disparity of two views with a fixed threshold, which is used to quantize the binocular psycho-visual redundancy and adjust the quantization parameter (QP) of the right view correspondingly. The proposed algorithm has been implemented in H.264/AVC video codec, and the experimental results show its effectiveness in rate control while keeping a good quality for the left view, and fewer bits are allocated for the right view so that the overall bit rate is saved by 7.2% at most without the loss of subjective visual quality for stereoscopic video.

In this paper, a discrete-time analysis of the third-order charge-pump based phase-locked loops (CPLLs) is presented in the presence of loop delay. The z-domain analysis of the closed-loop transfer function is derived and compared with the traditional s-domain method. The simulation results under SPECTRE show that, due to the sampling nature of CPLL, the traditional s-domain analysis is unable to predict its jitter peaking accurately, especially when the loop delay is taken into consideration. The impact of loop delay on the stability of the third-order CPLL system is further analyzed based on the proposed way. The stability limit of the wide bandwidth CPLL with loop delay is calculated. The circuit simulation results agree well with mathematical analysis.

In this paper, a hybrid adaptive compensation control scheme is proposed to compensate the friction occurrence and other nonlinear disturbance factors that exist in the high-precision servo system. An adaptive compensation controller with a dual-observer structure is designed, while the LuGre dynamic friction model with non-uniform parametric uncertainties characterizes the friction torque. Considering the influence of the periodic disturbance torque and parametric uncertainties, fuzzy systems and a robust term are employed. In this way, the whole system can be treated as a simple linear model after being compensated, then the proportional-derivative (PD) control law is applied to enhancing the control performance. On the basis of Lyapunov stability theory, the global stability and the asymptotic convergence of the tracking error are proved. Numerical simulations demonstrate that the proposed scheme has potentials to restrain the impact of disturbance and improving the tracking performance.

A measurement model based on torsion pendulum was established, in which nonlinear damping and nonlinear restoring force were considered. The calculation method of the moment of inertia was based on Hilbert transform. The motion of torsion pendulum showed the time-frequency characteristics due to the nonlinear factors, which were validated by the experimental data. The analytical signal was formed by Hilbert transform of the angular displacement signal of the test object. The moment of inertia can be computed by the instantaneous undamped natural frequency with Hilbert transform. Prior to the implementation of Hilbert transform, the empirical mode decomposition was used to filter the experimental signal. The moment of inertia of the test object was measured by the torsion pendulum system. The experimental results show that the relative measurement error of the moment of inertia was within 0.7%, which indicated the validity of the measurement method.

To investigate the activities of typical night-migrating birds under the light with various spectral compositions during autumn migration, 23 Siberian Rubythroat Luscinia calliope were tested under colorful LED lights with different wavelengths and mixed white at 100 lx. Using behavior response as an indicator, the quantitative relationship between the activity level of test birds and illumination stimulation duration was acquired. It was found that the visible light sensitivity of Siberian Rubythroat was the highest for the 478 nm turquoise and decreased towards the 622 nm red.